In a two-part special, the programme Talking Point explores the complications to recycling plastic and the reasons why exporting our plastic waste is getting more challenging — and uncovers a disturbing truth about recycled plastic.

And when it comes to increasing Singapore’s recycling rate in general, the “karung guni” (rag-and-bone) man could provide a solution.

The first challenge in recycling plastic is that there are many different types of plastic.

Generally, there are seven categories of plastic, each with different properties, said Tong Yen Wah, an associate professor in the department of chemical and biomolecular engineering at the National University of Singapore (NUS).

The six main categories include: PET, which is generally used to make bottles; polypropylene, a softer plastic that can be used to make food containers; and high-density polyethylene (HDPE), typically used to make shampoo and soap bottles.

In the seventh category, which Tong labelled “others”, there could be hundreds, even thousands of types of plastics. That is why these plastics are generally not recycled.

WATCH: The first episode — Do you recycle? Why it could be going to waste (21:59)